Rick Wilking / Reuters

On Monday, the Senate voted that U.S. troops should stay in Syria, a country where it has never authorized military force, and Afghanistan. There are “continuing threats from terrorist groups operating in Syria and Afghanistan,” 70 senators affirmed, adding that “the precipitous withdrawal of United States forces from either country could put at risk hard-won gains and United States national security.”

The nonbinding vote was a rebuke to President Donald Trump, who has urged drawdowns over objections from Senate Majority Leader Mitch McConnell.

And it highlighted Trump’s allies on the issue. Voting against the rebuke were the Tea Party–affiliated Republicans Rand Paul, Mike Lee, and Ted Cruz––and the entire field of Democratic presidential hopefuls who serve in the Senate: Cory Booker, Kirsten Gillibrand, Kamala Harris, Amy Klobuchar, Bernie Sanders, and Elizabeth Warren.

The vote is thus a portent of how the 2020 election may differ from its predecessor. In 2016, Trump defeated a large field of Republicans in part by differentiating himself as an opponent of expensive wars of choice. Like Barack Obama before him, he cast support for the Iraq War as stupid, and promised to redirect money from open-ended occupations of foreign countries toward jobs and infrastructure at home.

Democrats gave Trump a gift by pitting him against a hawk who not only voted for the Iraq War but also favored an ill-fated intervention in Libya. Hillary Clinton seemed likely to favor still more interventions if elected.

Monday’s vote suggests some recognition of that political error. In 2020, Democratic candidates who tout opposition to indefinite deployments to multiple Middle Eastern countries won’t merely better reflect a majority faction in their party; they’ll be in sync on that issue with many Americans who cast ballots for Trump.

How Trump will position himself remains to be seen. If he pulls troops out of Afghanistan and Syria, drawing a noninterventionist contrast will be harder. But if he runs for reelection with U.S. troops remaining in Iraq, Syria, and Afghanistan—and with the United States aiding Saudi Arabia’s dirty war in Yemen—opponents may argue that ongoing U.S. wars are exhausting resources that could be used to build marvels at home, while also convincingly casting themselves as more skeptical of interventions than Trump.

The obvious exception is Joe Biden, who has favored U.S. interventions in Serbia, Darfur, Afghanistan, and Iraq (though he reportedly opposed a later troop surge into Afghanistan, the unlawful U.S. intervention in Libya, and the unlawful deployment of U.S. troops to Syria).

In 2000, 2008, 2012, and 2016, the presidency was won by the candidate who touted the greater aversion to being the world’s policeman, despite critics who warned that America must not abdicate its leadership role in the world. In 2020, Democrats are very likely to simultaneously argue that Trump is intervening too much abroad and that he is undermining America’s leadership role in the world.

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